Modify the default startup level in Linux

In Linux, 0 to 6 are used to indicate different startup modes. each number indicates the following meaning: 0: The system is started normally and then shut down. 1: Single-user mode; 2: Multi-user mode; no

In Linux, 0 to 6 are used to indicate different startup modes. the meaning of each number is as follows:

0: The system starts normally and shuts down.
1: Single-user mode
2: Multi-user mode, no NFS
3: Multi-user mode with NFS
4: for use, leave a user
5: graphic interface mode
6: The system starts normally and then restarts.

1. according to the meaning of each number, we should be clear that we cannot select the 0 and 6 modes.

However, we generally only modify the three and five modes. In the 3 mode, the running level is changed to a quasi-normal level, which is pure command line.

2. modification level
Use vi to edit/etc/inittab
Go to id: X: initdefault

X indicates the mode you want to modify, except for 0 and 6, which can be entered by others, such as: id: 3: initdefault.

3. how to modify the incorrect configuration:

If you accidentally set the level to 0 or 6, use the following method to remedy the problem:

After the system is started, you will first see this interface. press any key before the countdown ends to enter the grub boot interface.

Enter 'e' in the grub boot interface, enter the next level, highlight the second line, and then enter 'e'

Enter 1 [single user mode] at the end and press enter to return to the upper level (single user mode startup will not read/etc/inittab)

Enter 'B' to restart the system